In a licensed-assisted access using Long Term Evolution (Licensed-Assisted Access Using Long Term Evolution, “LAA-LTE” for short) system, a device uses a channel resource according to a listen before talk (Listen Before Talk, “LBT” for short) rule. LBT is a carrier sense multiple access (Carrier Sense Multiple Access, “CSMA” for short) technology, and operation modes of the LBT technology include a load based equipment (Load Based Equipment, “LBE” for short) operation mode and a frame based equipment (Frame Based Equipment, “FBE” for short) operation mode.
In the LAA-LTE system, a device uses a clear channel assessment (Clear Channel Assessment, “CCA” for short) to detect a channel resource. When it is determined that the channel resource is occupied, the device backs off for one data frame period, and then performs a CCA again. The device occupies a channel resource to send data when it is determined that the channel resource is idle. When the existing device needs to use a channel resource, the existing device has a relatively low channel resource occupancy probability.